------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- -- -- -- S Y S T E M . T A S K I N G . E N T R Y _ C A L L S -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2018, Free Software Foundation, Inc. -- -- -- -- GNARL is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNARL was developed by the GNARL team at Florida State University. -- -- Extensive contributions were provided by Ada Core Technologies, Inc. -- -- -- ------------------------------------------------------------------------------ -- This package provides internal RTS calls implementing operations -- that apply to general entry calls, that is, calls to either -- protected or task entries. -- These declarations are not part of the GNARL Interface package System.Tasking.Entry_Calls is procedure Wait_For_Completion (Entry_Call : Entry_Call_Link); -- This procedure suspends the calling task until the specified entry -- call has either been completed or cancelled. It performs other -- operations required of suspended tasks, such as performing -- dynamic priority changes. On exit, the call will not be queued. -- This waits for calls on task or protected entries. -- Abortion must be deferred when calling this procedure. -- Call this only when holding Self (= Entry_Call.Self) or global RTS lock. procedure Wait_For_Completion_With_Timeout (Entry_Call : Entry_Call_Link; Wakeup_Time : Duration; Mode : Delay_Modes; Yielded : out Boolean); -- Same as Wait_For_Completion but wait for a timeout with the value -- specified in Wakeup_Time as well. -- On return, Yielded indicates whether the wait has performed a yield. -- Check_Exception must be called after calling this procedure. procedure Wait_Until_Abortable (Self_ID : Task_Id; Call : Entry_Call_Link); -- This procedure suspends the calling task until the specified entry -- call is queued abortably or completes. -- Abortion must be deferred when calling this procedure, and the global -- RTS lock taken when Single_Lock. procedure Try_To_Cancel_Entry_Call (Succeeded : out Boolean); pragma Inline (Try_To_Cancel_Entry_Call); -- Try to cancel async. entry call. -- Effect includes Abort_To_Level and Wait_For_Completion. -- Cancelled = True iff the cancellation was successful, i.e., -- the call was not Done before this call. -- On return, the call is off-queue and the ATC level is reduced by one. procedure Reset_Priority (Acceptor : Task_Id; Acceptor_Prev_Priority : Rendezvous_Priority); pragma Inline (Reset_Priority); -- Reset the priority of a task completing an accept statement to -- the value it had before the call. -- Acceptor should always be equal to Self. procedure Check_Exception (Self_ID : Task_Id; Entry_Call : Entry_Call_Link); pragma Inline (Check_Exception); -- Raise any pending exception from the Entry_Call. -- This should be called at the end of every compiler interface procedure -- that implements an entry call. -- In principle, the caller should not be abort-deferred (unless the -- application program violates the Ada language rules by doing entry calls -- from within protected operations -- an erroneous practice apparently -- followed with success by some adventurous GNAT users). -- Absolutely, the caller should not be holding any locks, or there -- will be deadlock. end System.Tasking.Entry_Calls;